hmm, hmm, hmm … I think I have to correct that. Is it really an original Rothko you’ve photograped ?!
The original White Stripe (1958) is almost square, and I just wondered about your format and some details aren’t matching with the print in my book and a google search also …
Anyways. It’s a nice one!
Maybe a White Center Version from the Reproduction-Gallery Website ?!

Shouldn’t the fact that there’s this much confusion between two different paintings be a bit of a sign pointing to a lazy repetitive painter? I never could handle this abstract simplicity sort of stuff. I file this guy right under Duchamp, and that guy makes me angry just thinking about him, lol.